One of the best three books is set for different majors in postgraduate entrance examination. Engineering majors take math 1 and 2, and economics majors take math 3. The difference lies in the difficulty and depth of the examination subjects and questions.

The subjects of the top scholar's exam are advanced mathematics, linear algebra, probability theory and mathematical statistics, which are the most difficult and deepest.

The examination subjects of number two are advanced mathematics and linear algebra, and the difficulty and depth of the questions are similar to those of number one, except for one examination subject.

The subjects of the number three exam are calculus, linear algebra, probability theory and mathematical statistics, and the difficulty and depth of the questions are the least.